He added: "A striking number of people in this country feel deeply uneasy. The utterly extraordinary, not to say ridiculous, claims about gambling as a means for regeneration simply obscure the fact of cost.

"Gambling is socially costly and whatever is said about supposed financial benefits, the creation of jobs and so forth in an area, one has to build in the cost.

"We expect industries to clean up their pollution.

"The gambling industry is profoundly costly, its human pollution in terms of promoting addiction, destroying family life and so forth, is manifest. The gambling industry needs to take responsibility.

"If we are concerned about mental health issues in the nation at large, then this particular question of gambling comes broadly under that head, and we need to see it as such."

Dr Williams said the Church should try to deliver people from the "slavery of addiction."

Alma Servant, a Manchester cleric and former casino worker, told synod members that casinos corrupted both punters and their staff.

"I watched gaming night after night after night," she said.

"It put me off casinos for life. They are dedicated to nothing else but money.

"Husbands or usually wives would turn up to try to get their husbands to go home.

"Sometimes this would be two or three times a week. You would hear whispers "Oh dear, he has lost his business".

"On one or two occasions I heard someone had committed suicide."

Canon servant added: "When staff see someone winning six or seven times their salary they are going to be corrupted.

"I was offered money for sex - several hundred pounds, a lot of money in the seventies.

"I said no. The next person said no. The next person said yes."

The synod strongly backed a demand that Mr Brown stop the construction of super-casinos and large casinos and called for churches to act to slow or stop planning applications for gambling palaces.

It declared grave concern at the way national spending on gambling has risen tenfold to £40billion in the past few years.

It also supported a new levy on gambling corporations to pay for education and treatment programmes for problem gamblers.

Supporters of the Manchester proposal said it would attract £265million of investment to the poor eastern side of the city and create 3,000 jobs.

The announcement that the supercasino will not go ahead is expected to be made formally in a few weeks.

It means that the plans for 40 new super-casinos, which were drawn up under Tony Blair and enshrined in the 2005 Gambling Act, have now been scrapped.